Effect of gait speed on clinical outcomes after crural and pedal bypass in patients with chronic limb-threatening ischemia

Objectives: Many factors affect long-term outcomes after open bypass in patients with chronic limb-threatening ischemia (CLTI). Ambulatory status has been suggested to be associated with clinical outcomes, but there is limited knowledge on the effect of gait speed on outcomes. The purpose of this study is to evaluate the effect of gait speed assessed in a 6-min walk test (6MWT) on outcomes after crural and pedal bypass in patients with CLTI. Methods: A retrospective analysis was performed in patients with CLTI who underwent a 6MWT at 1 month after crural and pedal bypass at a single center from 2014 to 2021. Comparisons were made between those with high gait speed (HG group, 6-min walk distance (6MWD) > 288 m) and those with low gait speed (LG group, 6MWD <= 288 m). The primary endpoint was survival, and the secondary endpoints were graft patency, limb salvage, wound healing, major adverse cardiovascular events (MACEs), and hospital outcomes. Results: Of 104 patients with CLTI who underwent a 6MWT after crural and pedal bypass, 46 (44%) and 58 (56%) were placed in the HG and LG groups, respectively. The LG group was older (p < .001), had more female subjects (p = .006), and had a higher prevalence of cerebrovascular disease (p = .042) and tissue loss (p = .007). The median follow-up was 36 (22-57) months. The HG group had significantly higher 3-year primary patency (65% vs 42%, p = .013), 3-year secondary patency (87% vs 66%, p = .018), 3-year overall survival (89% vs 58%, p < .001), and 3-year freedom from MACE (79% vs 67%, p = .039). The 3-year limb salvage and 12-month wound healing rates did not differ between the groups. Conclusions: Gait speed in patients with CLTI after crural and pedal bypass was associated with survival, freedom from MACE, and graft patency but not with limb salvage and wound healing. A detailed study of walking ability in these patients may be needed in the future.